text:
How can I recognize Taylorcraft BCS-12D-4-85?
I'm perfecting my logbook and can't name the subtype of the aircraft I've flown. Some directories says it was built in 1946 and is a BCS-12D on floats. Others say it is a BCS-12D-4-85 which according to Wikipedia was built in 1949.
Is there a way to know which aircraft I was training in?

Do you have the N number?

It was the N43459

That airplane is registered as a 1946 BC12-D per the FAA's N number lookup service.  This indicates that it came from the factory as a BC12-D but then may have been converted later.  Conversions don't change the subtype.
As far as recognizing specific subtypes of old airplanes, good luck!  Many old, popular planes have undergone all kinds of conversions.  Bonanzas built as early as the 1940s can be converted to look like a late model V35B from 1981!  There are even mods to remove the V tail and replace it with a "normal" tail.  My point is that determining subtype from appearances alone may be impossible.
Link below...
https://registry.faa.gov/aircraftinquiry/NNum_Results.aspx?NNumbertxt=N43459

So you're saying at least that when it was made it was a BC-12D and could have been converted later? also check this: https://www.aopa.org/news-and-media/all-news/2011/december/01/challenges-river-dance

I mean, sure...it now meets the form and function of a BCS-12D-4-85 and that's all that should count. Someone did, after all, spend considerable energy installing floats (BCS-12D), an extra side window (-4), and an 85hp engine (-85). It's not possible that it is a 1946 model and a BCS-12D-4-85 though, or at least that it is a factory built BCS-12D-4-85. I did my tailwheel in a 1946 7AC converted to a 85hp 7DC and I think I logged it as 7AC/DC but it really was, for all practical purposes, a 7DC.


text:
Can the FAA allow a foreign training center to add a type rating to an FAA license?
I have an ICAO license and an FAA one with the same type rating on both. I have done the initial training through the FAA in the US, but was able to validate the sim, training center and the DPE to get the type on my other ICAO license as well.
Now I wish to do the same, reversed - get an initial for a different type on my ICAO license and have the FAA validate it so I will have it on my FAA license as well.
Is that possible?

Training centers do not issue type ratings, examiners do. To validate foreign ratings in your FAA license you have to submit the request and supporting documentation to the FSDO closest to you. They will tell you if it is possible to add the rating to your license based on reciprocal agreements.

Good point about the examiners. Also, is there any FAR 14 CARs that deal with this?

I believe that what you have to do is find a FAR 142 school to help you work through this. There's no automatic way to get the rating added to your FAA ticket, you have to show evirence of PIC time, be fingerprinted if you haven't had that done already, get a background check good for 180 days, and then go through some training. Even so, i think you only get SIC privileges added to your ticket; from what I can see there's no way around that.

SIC is ok at this point since I only hold a CPL and following EASA rules it is restricted to SIC anyway. When you say FAR 142 school, you mean one in the US or in Europe (if that exists even)

I know that FlightSafety runs Part 142 schools in various worldwide locations, including Europe, Singapore, Saudi Arabia, etc. The current list of training centers operating under Part 142 is here: https://www.faa.gov/pilots/training/part_142/media/Active_FAA-142_Training_Centers.pdf

Well, there are a few moving parts to the answer to your question.
This depends on your situation and that of your training center.
First, let's clear up a little bit of misunderstanding that many people have about DPEs and TCEs:
Under Part 142, you need both a Training Center AND a Training Center Evaluator (TCE) to issue a type rating. A TCE can not issue type ratings absent the authority of the specific Training Center (or centers) for which they have been authorized by the Training Center's POI (Principal Operations Inspector). If I am a TCE for ABC Training Company, I cannot go give checkrides for XZY Training Company without formal written authorization from the FAA.
This is completely different than being a Designated Pilot Examiner (DPE) who can type you in any aircraft for which he is authorized anywhere in the US (as of October 2018). He does not have to work for a training center to complete checkrides. However, in order to use a DPE, you must complete the checkride in the actual aircraft. There are some DPEs that are also TCEs but the authority under which they issue the type rating is based on their authorizations from the FAA. For example, one of our TCEs is also a DPE. The FAA allows him to conduct type rating checks under Part 142 as a TCE but not under Part 61 as a DPE.
Flight training facilities that operate in foreign countries under US FAR Part 142 regulations can (and do) issues type ratings on US certificates all the time. Flight Safety is one of those companies. The have Part 142 approved TCEs on staff to conduct FAA checkrides for those type ratings.
IF (and I say IF) the training center where you train is approved by the FAA to issue type ratings under Part 142 then they could issue you a type rating on both of your certificates upon completion of your training and checking. We do that is the US for various other countries.
If your training center does not have that authority and you still want the type rating on your US FAA certificate, then you have a couple of different option depending on how your US certificate was issued to you. If your US certificate was issued based on your foreign certificate (ie - not a stand-alone FAA certificate), then you can go through the foreign certification verification process, take and pass the Foreign Instrument Written test and then the FAA will issue you a new private pilot certificate based on your foreign certificate with the type rating attached.
If you hold a stand-alone US FAA certificate, and you attend a non-FAA approved training center, there is no way (that I am aware of) to get your foreign type rating added to your stand-alone FAA certificate.  You would need to take and complete a US FAA approved Part 142 type rating program or a part 61 in-aircraft program.
Also keep in mind that if you hold a stand-alone FAA certificate, the FAA will allow you to surrender that certificate and to go through the foreign certification verification process (including taking the foreign instrument written) to get a new private pilot certificate based on your foreign certificate with the type rating attached.

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Are the terms "Coupled approach" and "Hand flown approach" strictly defined?
I was looking on SE and also Google for the answer, but couldn't find anything. My question is when to log an approach as coupled or handflown? All of the approaches I fly are CAT I but the aircraft's autopilot has a coupled approach mode

Why would you need to log an approach as one or the other? Either way, you flew the approach. If one or the other is needed to meet some requirement, then read the wording of that requirement.  But other than a small handful of very specialized situations (which specify clearly what's required), I can't recall any general requirement for logging an approach as coupled or hand-flown.

@RalphJ some carriers require hand flying approaches occasionally to maintain skills, and presumably they'd want that logged to determine compliance.

@StephenSprunk In that case, each of those carriers would define what they consider to be “hand flown” — FAF to DA, 1000’ to DA, whatever.  There is no single “strictly defined” that necessarily applies in all cases.

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What is a Ground Power Dispatch Switch?
I've been going over the new Master Minimum Equipment List (MMEL) for Textron Aviation Model 500 Series Citations and on page 36 a Ground Power Dispatch Switch is mentioned but I can't find any information or pictures of it online.
Can someone explain?

The Citations have an auxiliary battery in the nose that lets you power up limited avionics, like a comm radio and one of the FMS units and displays, to allow you to get your clearance and program the FMS before engine start, in the absence of a ground power cart, without having to deplete the main battery.  It's controlled by the Ground Power Dispatch Switch.


text:
How is paint embrittlement countered in high altitude aircraft?
There are cases of aircraft that are not designed for high altitudes that can still fly there and as a result the paint on these aircraft "falls off".
Although most aircraft have paint that is chosen to work up to their maximum flight altitude (that is mainly limited by the engine and by aerodynamics), sailplanes are an example of aircraft that do not have a fixed maximum flight altitude. As long as thermals push these aircraft higher, there are few limiting factors for their maximum altitude, as the necessary lift and thus velocity at high altitudes is not as significant as other aircraft since they have a large wing area and low wing loading.
My question thus is not centered around the aerodynamic limits and answers such as "it is selected to work up to its maximum flight altitude" but rather around the process of the selection of compatible paints. It may include design and selection considerations for civil aircraft at 10.000m AGL and for high altitude military fighters. Does the paint over the aircraft surface change due to additional influences e.g. front edge heating?
If necessary, an overview of the different paint types used (at certain altidudes) would be appreciated.

For me it is just cohesion force ("glue" of paint) vs pressure. Note paints could contains water and bubbles of air. Possibly it is not just the paint, but the method to apply it.

well, this simple approach is not sufficient for me, as it does not tell me which paint I should use and what differences there are. Usually the basics are pretty simple e.g. an airplane is something with a fuselage, wings and engines. But....

You should check with paint manufacturers and eventually test it on your own. I do no think there is a list of allowed paint, just requirements that either should be given by manufacturer, or by a testing/certifying authority. Note: the field is complex: usually paints are mixed with stabilizers and UV screen: pigments are often not so stable.

There are 3 critical areas one may wish to address with paint:  the formulation of the paint, how it is attached to the substrate, and the properties of the substrate.
The substrate may expand, contract, bend or twist with heating, cooling, or stress.
The attachment of the paint to the substrate is crucial to durability.  Surface preparation includes cleaning, deposition of a chemical coating such as chromate, or primer.  This is a make or break step that should not be ignored.
Finally the paint itself.  Bare bones paint formula is solvent, pigment, and resin. The solvent evaporates, leaving the pigment (color or shade) and the resin, which is essentially the coating.
Factors such as temperature, flexability, hardness, weather and UV resistance must be considered.  The closer the properties of the paint are to the substrate the better.
I would find out what the airliners use.

Thank you for the brief summary of factors to consider. It is true that airliners are a good reference, but I wonder if the same paint is also viable on aircraft flying in the stratosphere. Also how does the paint layup change in different designs/design altitudes?

Once the paint is dried and cured, air pressure is not a factor.  Extreme temperature will be, so you want a flexible coating that expands and contracts.  UV resistance is also very important going high.  A "baked on" coating, silicone or fluoropolymer based, may be worth a look.  This application will have a lot of sources on the net.

Airliners have been painted with polyurethane top coat over epoxy zinc chromate primer since the 70s/80s.


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Minimum turning radius (or maximum banking angle) of a commercial airplane
The context of the work: in an ATC model, we currently have a graph model to set the routes for different aircraft. We want to improve its precision by generating more nodes for each route and in order for these nodes to be feasible (i.e., reachable by the aircraft) you do that embedding the Dynamics of the vehicle in the generation of nodes.
Bottom line, I need some "citable" source where I can find the values for the minimum turning radius of an airplane. Since it is preferrable to be conservative than to implement something that cannot be done, I am looking for "large" commercial aircraft as I understand they will set an upper bound. That said, it is a research work so it doesn't need to be "the largest aircraft that ever cruised over the airspace", just some reasonably big airplane that is commonly used: Boeing 747, Airbus A380,etc..
Note: only Civilian flights are considered, therefore military crafts are not relevant here

Keep in mind this turn radius depends on airspeed, which in turn depends on altitude (that's why enroute holds are so dang big)

Depends - do you want them to pull several G's to make a small radius or do you want to avoid having a few hundred complaining passengers?

Don't have a source to cite, but 30 degrees of bank is the max anybody is going to use for ATC purposes.  Plug that in with your assumed True Air Speed, and you can get a turn radius (which assumes still air).  Allow for wind effects as well, since 100 knots tailwind/crosswind will make for a larger effective turn radius than just the TAS alone. There is probably someplace in the AIM or an ATC regulation that mentions the 30 degrees value, although offhand I don't know where -- sorry about that.

If you look for emergency procedures, see this and this question.

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What is the speed during push-back?
What is the usual or maximum speed during the push-back procedure of large commercial aircraft (say, B737, B787)? Is it fixed or dependent on the aircraft type or weight or anything else? Is it different for towbarless vs. towbar procedures?

There is no regulatory guidance on how fast (or how slow) an aircraft must move during the pushback. Furthermore, there are many opinions (see below) on how fast an airplane moves during pushback.
If you watch a pushback, you will notice that ground personnel known as wing-walkers* will walk alongside the aircraft, at the wingtip, during pushback.  The normal speed of humans walking is 3-4 mph, which can surge to 5-6 mph for short distance.
The speed is not fixed. It is dependent on all the factors you mentioned plus the experience of the tug driver and ground crew as well as size of the airplane and its weight. It takes longer to accelerate a large airplane to this speed, and it is harder to slow down a large airplane.

* ICAO Annex 2 Volume 5 (Appendix 1-5) and SA CATS 91.05.1 (5)
See also:

airliners.net / Pushback-speed Limitations?
pprune.org /  Pushback and Towing - Time

The speed of the pushback will vary depending on surface conditions (wet vs dry), as well as whether or not the aircraft has already started the engines, as the pushback vehicle will have more difficulty pushing against the weight of the aircraft and the idle engine thrust. The presence of a slope can also have an effect.

Pushback speed might be faster or slowing depending upon whether your pushing with or against the rotation of the Earth.

@ksea Normally, engine start is delayed until after pushback.

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What is the purpose of long endurance test flights?
Well known is the last long endurance test flight by a Boeing B787-8, which drew its shape in the air for 18 hours while on a long endurance test flight: https://www.wired.com/story/boeing-787-8-drawing-test-flight/.
What exactly is the purpose of these long endurance test flights? What is tested, what shall be proven? - surely not that the aircraft can actually stay in the air that long, because that test flight happened long after the introduction of this type into the market...
On a side not, does every commercial airline type have to undergo such an endurance test flight?

Bragging rights?

This particular test flight tested the engines, not the aircraft:

At 15:38 local time N7874, the fourth 787 built, departed Boeing Field
  in Seattle for an 18-hour, 22 state test flight. The crew spent the
  overnight hours above the United States performing ETOPS testing on
  the new Rolls Royce Trent 1000 TEN engine, which will power the
  787-10.

https://www.flightradar24.com/blog/boeing-uses-a-787-to-draw-a-787-dreamliner-during-etops-test/

So why not test these engines on the ground then? What's the benefit of using a test flight?

@Stefan You can then ask the following questions: Why use engine testbed aircraft (search this term on Google) at all if you can test engines on the ground. Heck, why even have test flights at all? we can test all aircraft in a wind tunnel. The answer to both questions is that you can't test everything on the ground, especially not engines. Specifically, ETOPS test flights presumably involve flying on a single engine due to the nature of ETOPS. See https://en.wikipedia.org/wiki/ETOPS#Approval

@Stefan an engine on the ground has a different atmospheric makeup, pressure, temperature, and doesn't have air being forced into it at 560mph.

@stefan, for smaller engines, like those for business jets or small fighters, testing like this can be conducted on the ground in special facilities (e.g. http://www.arnold.af.mil/About-Us/Fact-Sheets/Display/Article/409293/propulsion-wind-tunnel-facility/).  However, the mass flow rate of an engine like the Trent 1000 is around 1000 kg per second.  Building a wind tunnel of that size would be orders of magnitude more expensive than just flying the plane around for a few hours (especially if you already own a plane)


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When may pilots leave the flight deck during flight?
Are there regulations as to when commercial pilots may leave the flight deck during flight, i.e. due to physiological needs? Anytime when it is practical (obviously it would not be practical during take-off, approach and landing), or only during the cruise period (i.e. controlled resting only allowed in cruise)?

FAR 91.105 and also FAR 121.471 are applicable. The airlines may have SOP's that identify when a crew change can happen, but I don't know of any FAR that says only during a specific phase of flight.


text:
Does operation under ETOPS rules require additional procedures in flight during the ETOPS segment?
During Extended-range Twin-engine Operations (ETOPS), are there any special procedures pilots have to follow? I am asking for specific procedures / tasks during the ETOPS segment of a flight, not what happens before entering the ETOPS segment (check ETOPS items on MEL, calculating Equal Time Points, check communications, ...). Maybe additional checks (engine, fuel, oil) during cruise flight that are not done when not operating under ETOPS rules?

Most of the action for ETOPS flights takes place during planning and dispatch stages- the planning for alternate airports, gathering of weather reports for diversion cases etc. Before ETOPS entry point, the weather reports are updated and checks are made; after that there are no 'special' procedures to be followed during a (normal ETOPS) flight.
From Airbus ETOPS Guide:

3- IN-FLIGHT ETOPS PROCEDURES
b) Weather update
− after ETOPS Entry Point:
The crew should continue to update the weather forecasts and reports
  for en-route alternates.
As for a normal flight, the crew must make every effort to keep
  themselves informed on the weather at the destination and the
  destination alternate.
c) Fuel monitoring
The procedures normally used as per airline policy is also applicable for
  ETOPS.
This is true even for flights where ETOPS fuel planning is the limiting factor.

In case of diversion (say due to an engine failure), the PIC will take a decision like any other flight, though he/she cannot fly beyond the nearest suitable airport.
One way of looking at this is that the main purpose of ETOPS certification is to improve the robustness and reliability of the design and operator to a level that the ETOPS flight could be conducted like any other normal flight in the ETOPS segment.

Some airlines are required to keep their APU running en-route on an ETOPS mission. This probably only applies to 2 engine aircraft. The only one that doesn't that I am aware of is Alaska Airlines.

Can you provide sources?

Here you go. AC 120-42B and you can visit this thread for more info. https://www.avsim.com/forums/topic/351778-ng-etops-questions/


text:
From which ATC station is push-back clearance requested?
When parked at the gate that requires a push-back onto the taxiway, from which ATC station is the push-back clearance requested? Is this the ground or apron station, or is that still departure clearance delivery station (as they better know the slot times, etc.)?

At controlled aerodromes, the aerodrome control tower is responsible for separating aircraft on the maneuvering area (from other aircraft, and from obstacles, vehicles etc.). If a pushback is done onto a taxiway which is a part of the maneuvering area, the aerodrome control tower must approve this first. At large aerodromes, there are different tower working positions, operating on different frequencies and with different callsigns. So the "which exact ATC station" question really varies from airport to airport. You might talk to "xx tower", "xx ground" or something else entirely.
Note that at many airports, the gate area (apron) is NOT a part of the maneuvering area. Technically speaking, ATC is not responsible for separating aircraft outside of the maneuvering area. Instead, pilots, tug drivers, vehicles and other persons on the apron follow different priority rules when a pushback is required (traffic laws normally state that vehicles shall yield to aircraft; the rules of the air have rules regarding aircraft right-of-way).  However, some major airports have designated positions for coordinating this effort, which - from the pilot perspective - looks just like ATC. They operate on a VHF frequency, and typical callsigns are "xx apron" or "xx ramp". Note, however, that such stations do NOT provide air traffic control - technically, they provide advisory service, and they are not responsible if a collision occurs, because ATC separation is not provided outside the maneuvering area. Persons staffing such positions generally do not have to be fully qualified air traffic controllers (this will vary from country to country), and are sometimes employed directly by the airport, instead of an air navigation service provider.
In summary: if the pushback occurs on the maneuvering area, the aerodrome control tower has to approve it. If not, no ATC approval is required, but there might still be other stations coordinating pushback.

It depends on the airport.
I don't have a statistics, but from what I've seen, usually it is the ground station, as they coordinate the movement of airplanes on the ground, and they have an idea if the runway lineup queue is long, or another plane is taxing behind.
In non-busy airports (the ones which only get a few flights per day) the same guy might be the clearance delivery, ground and tower at the same time. So the pilots are basically talking to the same person.
KJFK is one exception where push back is coordinated by "ramp", as you can hear for yourself in this ATC recording with Air France 011 Heavy who was apparently was not very familiar with that airport's operations.

IF the gate is controlled by a Ramp Control, then they will issue the pushback clearance; otherwise it's Ground Control. Or at some gates / some airports, push may be "at pilot's discretion" and not controlled by ATC at all.

Most likely either ground control or if there is a designated frequency for a secure apron movement, that would be used.  Check the A/FD entry for the airport or ATIS for further information.


text:
Is the pilot required to keep visual lookout during IFR operations in VMC?
During VFR operations, the pilot must always self-assure separation from other aircraft, and thus must maintain a visual lookout all the time.
For IFR operations but in VMC, are there any rules as to pilot visual lookout? Is the pilot still required to maintain visual lookout (might be difficult in clouds, though...). Even if ATC assures separation, some objects such as drones may not be known to ATC, so ATC cannot provide separation...

“Even ATC assures separation”, actually, it assures separation between IFR flights, but depending on airspace class may or may not assure separation from VFR ones.

Knowing ATC's at fault as you fall to earth after a collision is small consolation. You should always keep a lookout no matter what the regs say.

Possible duplicate of Who is responsible for aircraft separation in IFR (limited/no visibility)?

Not just drones but parachutists, very small manned aircraft such as powered parachutes and ultralights, and so on. Also there are areas without radar coverage. And even if radar does spot another plane, it won't necessarily report that plane's altitude accurately if the plane doesn't have a transponder. Also, other planes not controlled by ATC may make sudden maneuvers or deviations and there's no guarantee ATC will get a clear channel to report it to you in time.

You didn't mention which country or jurisdiction you're asking about, but in the US 14 CFR 91.113(b) says:

When weather conditions permit, regardless of whether an operation is
  conducted under instrument flight rules or visual flight rules,
  vigilance shall be maintained by each person operating an aircraft so
  as to see and avoid other aircraft

I assume other countries have similar regulations but even if they don't, it's still common sense and good piloting to keep a visual lookout whenever possible.

See and avoid is the mantra in every jurisdiction I know of, whether IFR or VFR.

Yup! In some airspaces, you will have IFR and VFR without separation to each other and will only receive traffic information where available, e.g. class E airspace in Germany.

"See and be seen" is another good one.  e.g. landing lights in daylight.  it's just as important do what you can to give the other pilot a chance of spotting you (and maintaining situational awareness through judicious use of the radio) and looking out yourself.

ATC assures separation...

This is a pretty critical misconception. ATC does not necessarily provide separation, just because you are flying IFR. Let's do a quick recap of the different airspace classes.
In class D, ATC will provide separation between two IFR flights, but will not separate VFR flights. All flights are provided with traffic information, and must avoid collision by means of traffic information and a visual lookout.
In class E, ATC will provide separation between two IFR flights. Traffic information about VFR flights will be provided if possible - but VFR flights can fly in class E without any radio contact, so ATC might not know about all flights. It is up to the pilots to avoid collision by using traffic information and keeping a visual lookout.
In class F, no separation is provided, regardless of whether you are flying IFR or VFR. ATC will provide advisory service towards other IFR flights, and traffic information about VFR is possible.
In class G, no separation is provided. Traffic information can be provided as far as practicable. (In some countries, you are not allowed to fly IFR in class G airspace - but this varies).
So yes, pilots are expected to keep a visual lookout, also when flying IFR. Obviously, in bad weather, this does not really apply. This is also the reason almost all aircraft are equipped with anti collision lights and navigation lights - so that other flights can see them.
Additionally, ICAO Annex 2 (Rules of the Air) states:

An aircraft operated on or in the vicinity of an aerodrome shall, whether or not within an aerodrome traffic circuit, observe other aerodrome traffic for the purpose of avoiding collision.

Note that there is no mention of flight rules. This procedures applies to "An aircraft" - that is, any aircraft.


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Is altitude information included in filed flight plan?
When the dispatcher produces and files the flight plan for a scheduled flight with ATC, are the determined optimal cruise altitudes part of the flight plan, or does the flight plan only contain lateral route information?

The flight plan contains the requested cruise flight level, as well as step climbs or level changes along the route in the route field.

Example 1:
(Image Source: skybrary.aero)

Example 2:

SAM UN621 BASIK/N0412F330 UZ150 BADUR/N0426F340 UN472 ARE/N0424F350 UN864 PIMOS

Fxxx being the requested flight level.

In case of level changes in FPL how is pilot executing that change (what how will profile look like)? E.g. imagine flight is using F300 and pilot sees folowing sequence ... AAAA BBBB/F340 CCCC... Does this mean he will: 1) gradually change altitude between AAAA and BBBB, 2) between BBBB and CCCC 3) He will change altitude exactly in BBBB  as quickly as possible?

BBBB/F340 means that F340 shall be already obtained at BBBB. So he will request a climb between AAAA and BBBB.

The ATC Flightplan (FPL) does not directly contain the optimum cruise levels for a flight. These levels are calculated and printed in the Operational Flightplan (OFP).
The FPL does contain the requested cruising levels for the flight along its planned route. The requested flight levels (RFL) in the FPL will often be quite close to the optimum cruising levels, but they are unlikely to be exactly the same. This is because there are certain regulatory restrictions regarding which levels can be requested along certain routes. For example, semi circular rules state that flights in specific directions must be flown at a specific range of cruising levels - for example, all westbound flights must fly at "even" flightlevel (FL300, 320, 340, etc.) - the exact rules vary from place to place. There can also be other restrictions in place as a result of active military areas and ATC capacity.
The optimum cruising levels are usually a part of the OFP, and the current optimum level is also shown in the flight management computer in the cockpit. Air traffic controllers do not have direct access to these levels, but pilots will routinely request a level change if their RFL from their FPL deviate significantly from their optimum level.
To recap - the ATC flightplan does contain one or more requested levels for a flight, but these levels are not just based on the optimum performance, they also have to comply with published regulations and restrictions.


text:
Why are callouts of changes in the Flight Mode Annunciator not automated?
With many airlines it seems to be standard that the Pilot Monitoring observes the Flight Mode Annunciator (FMA) and calls out any changes in the autopilot mode displayed on the FMA (I guess to raise awareness to the new or armed flight mode). Why are these announcements not automated (i.e. computer generated voice like the altitude announcements during final approach)?

On some platforms like the G650, a chime will sound and the mode indicator will flash if the mode change is not due to pilot action (as ymb1 points out, calling out flight mode changes due to pilot action is generally not helpful).


text:
Does the pilot in command always sit on the left seat?
Are there any rules (i.e. airline-specific) or regulations (laws) that state that the pilot in command (PIC) must sit on the left seat in commercial airliners?
This question specifically asks for rules concerning the PIC who is not neccessarily the highest ranking crew member (as I think that a check captain may sit in the right seat when checking a captain).

Related: http://aviation.stackexchange.com/questions/15147/why-does-an-airplane-captain-sit-in-the-left-seat?rq=1

In the TBM 850 there's an autopilot limitation that requires a pilot be seated in the left seat for autopilot operation. http://bit.ly/2kBZivr

Funny fact, in helicopters is the right side. Rambo made a mistake in one film :)

No, the PIC does not always sit in the left seat, and there's no regulations about it. Most airplanes are configured so that the primary pilot would sit on the left, however there are military trainers (the Slingsby Firefly comes to mind) which have this on the right so that the pilot has the throttle on the left and stick on the right as single seat military jets have. Helicopters have the pilot on the right, not the left.
In any case the PIC is not necessarily the handling pilot, instructors usually sit on the right and are often the pilot in command.

Similarly, virtually every GA airplane is designed to allow a PIC (a CFI training a private pilot student, for example) to fly from the right seat.

A book written by an Army helicopter pilot, about his service during the Vietnam War, pointed out that where the aircraft commander (pilot-in-command) sat depended on the mission.  USUALLY, the helicopter PIC sits in the right seat, so he doesn't have to climb over the collective stick as he gets in and out.  For SOME missions, he needed the better ground view out the chin windows on the left side, and so he sat in the left seat (and, presumably, grumbled about the collective).

GdD is correct BUT this is not to give the impression that the pilots can just swap seats from leg to leg at will. Most if not all US airlines operations procedures now require seat specific qualification because the the duties are different for each position.  Check Airmen who train pilots do sit in the right seat when training a Captain but they have to take a checkride in that seat to demonstrate proficiency in addition to their regular left seat checkride. When I started my career in the early 1980's this wasn't required.  I was a Boeing 727 Flight Engineer and at the end of a month they were out of Co-Pilots to fly so I was with two Captains.  I remember that entire trip looking up front and seeing many switches normally set by the co-pilot out of place.

Nice answer -- welcome to Av.SE!  We could do the same thing in the USAF -- "you're qualified in the left seat, so you're qualified in both seats" and it wasn't all that common to find somebody who could actually do the right seat job all that well, even though he was allowed to. Far better to fly with a "real" copilot in almost every case!


text:
Does the Airbus A350 have an Automatic Emergency Descent System?
In 2009 Airbus went public with a new feature in the Airbus A350, an Automatic Emergency Descent (AED) System.
The system would detect a rapid depressurization and, after a defined waiting time, would initiate an automated descent if the pilots failed to respond to the respective alert (i.e. in case of pilot incapacitation).
I found some presentation slides from 2015 on the topic but haven't heard anything on that system since. Does anyone have additional information: is it a standard feature now on the A350, is it optional, or was it not pursued any further? If not, for what reasons?

Now I'm wondering how many separate things need to break on the plane before this system performs an unplanned emergency descent into terrain.

On a crew bus the other day at American. Mgmt type said it like this. If the Cabin Alt goes above 14000, the aircraft starts a 15 sec timer. If no intervention from the crew, it initiates an Emergency descent. Power back and spoilers. Vmo/Mmo-10kts. It even changes the squawk to 7700. The aircraft will level off at 10,000 or Grid MORA whichever is higher.
Was also told that it will auto respond to a TCAS RA if the autopilot is on.

welcome to aviation.SE. if possible, we prefer autoritative sources, not "a guy told me". If you could find some sources to back up your answer it would improve substantially.

So an aircraft eastbound from California could level off at 16,000, 18,000 feet, somewhere in that range if Grid MORA calls for that while in the vicinity of the Rockies?


text:
Is the Auxiliary Power Unit used after landing when ground power is available?
Assuming the airport provides ground power at the gate, will the Auxiliary Power Unit (APU) be started and used after landing? If not, I guess the engines will only be shut down when the Ground Power Unit (GPU) is connected. In this case, how do pilots know that the ground power is connected, so that they can shut down the engines?

Responding to the first part of your question about starting the APU at arrival.
Soon after landing the APU is usually started to provide a seamless electric power transfer and cabin thermal management (cooling and heat) prior to main engine shutdown.  Otherwise the aircraft will need to be plugged in electrically and have a large duct attached to provide cabin comfort.

If the APU is operational we always start it before we arrive at the stand. One of the main reasons for this is to ensure that we have an active bleed source before we shut down the engines. Why do we need a bleed source? Because when the engines are at idle power (during start up and shut down), in rare occurrences excessive fuel in the combustion chamber can cause the fuel to light up and send flames through the engine exhaust. We call this a tailpipe fire https://www.skybrary.aero/index.php/Tailpipe_Fire. If a tailpipe fire occurs, you need to ventilate the engines and for that you need a bleed air source. The APU when started can provide it immediately and help to get rid of the excess fuel by turning on the starter without switching on the fuel.
In airports that require the shut down of the APU (mainly to minimize noise pollution) we still turn it on so that we have power available until the GPU is connected. The GPU will be connected by the ground crew once the engines are turned off. Once it is up and running, the engineer will contact us using his headset and will ask to turn on the external power and shut down the APU. As soon as we get the green light we turn on the external power and turn off the APU. To cool the cabin, usually an air conditioning unit is also connected to the aircraft.
So, what if the APU is inoperative? In this case, we always notify the station we are flying to about the status of the aircraft. We simply tell them that our APU will be inoperative and we require the GPU on arrival at the gate. At the gate because with engines started no one can approach the aircraft. So, we use hand signals to alert the ground to get the GPU connected. The hand signal for GPU connection is shown in the picture below. You basically make a T signal using hands.

(Source https://studyflying.com/marshalling-hand-signals-for-aircraft/)
To allow the connection, we shut off one of the engines. In most airliners, the number two engine is shut down, so that the ground crew approach and can connect the external power from the right of the aircraft. With the GPU connected the remaining engine is shut down. If you were to shut down the engines without connecting the aircraft to a power source, the aircraft will revert to the batteries which will turn off all the lights and most of the cockpit displays. It is not what exactly you want to happen.

You say "we". Is that pilots in general, pilots of a specific type of aircraft (B737, A320, etc), pilots at your airline, or some other "we"?

@FreeMan the standards in most airlines is very similar. So, the "we" here refers to generally all airline pilots.


text:
Why do some airports park the aircraft backwards at the gate?
(YouTube) Push-in at Dortmund Airport.
While at most airports, aircraft park at the gate facing the building, there are some airports that park aircraft backwards, e.g., Dortmund Airport (shown above), and London City Airport. After arrival and engine shutdown, aircraft are then pushed back into their parking position.
What is the benefit of parking aircraft backwards?

This is the first time I've seen aircraft being pushed back into their parking position. Though I am no expert, my experience as an airport operations supervisor (in a past life) would lead me to believe that the most significant advantage is that an aircraft could then depart the parking location more quickly under its own power (versus waiting for the pushback).
The most labor intensive portion of turning an aircraft (from a ramp crew perspective) is the dumping and loading of the cargo pits. This typically occurs as soon as the aircraft arrives to the gate. Thus, there is some potential for operations efficiency by performing the pushback on the front end, since the ramp crew is already there. Once all ground actions are complete, the majority of the ramp crew could then leave for another flight (perhaps leaving one behind to disconnect ground power, pre-conditioned air, and to guide the aircraft out of the apron).
The aircraft illustrated either use built-in aircraft stairs or air stairs; this arrangement would not be possible using a conventional passenger loading bridge, as they are typically designed for aircraft parked nose-in.


text:
What is the typical touchdown angle of a large airliner?
Following up on my previous question about the typical vertical speed during the touchdown, I am now curious about the typical touchdown angle.
Airliners touch down with the main landing gear first, and only then the nose wheel. Hence there is some angle between the runway and the aircraft's body longitudinal axe. Let's assume that the runway is flat and that there is no slope in the runway.
Of course, the angle depends on many, many factors. It's theoretical maximum would be limited through a tailscrape event - and since aircraft are different in length, there is no general answer to this one. Theoretical minimum would be 0 degrees (or less, but then we have a nose wheel first landing). But, as highlighted in answers to my previous question, is there any information in operating manuals about typical angles, or can pilots provide some insight into which angle they are trying to achieve during touchdown?
Besides the typical angle, is there an optimum angle for any reason?
Again, I am not interested in the approach, only the touchdown after the flare.

One primary restriction is called "the angle on the deck". This limitation prevents them from scraping the tail, and on some aircraft with engines in the tail (i.e. fuselage blocks the 727 #2 engine) keeps the air stream straight enough for full power. The B727, DC10, and most stretch versions of aircraft will have deck angle limitations. Inlet air angle was among several problems of the Comet, this was attributed to one crash and several near catastrophes.

@jwzumwalt: Two crashes, actually, although only one of those was fatal.


text:
How are arriving aircraft assigned to runways?
A similar question to this one was asked before, however my question is not about who assigns runways to arriving aircraft, but what the reasons behind those decisions are.
As an example, let's look at Frankfurt EDDF with four runways (map here). 18 is only used for departures. Of the three parallel runways 25L/07R, 25C/07C and 25R/07L, one is usually also used for departures, leaving two of them for arrivals (from my experience, usually 07L/25R because it's for landings only, and then 07R/25L).
Besides runway length (as discussed in the above referred question) and width, what factors into the decision of which of the two arrival runways an arriving aircraft is assigned? (and other than that it is regulated that certain types may not land on 25R/07L such as A380, B747).
Can airlines / pilots request a runway? In particular, landing on 25R in Frankfurt should be pretty unpopular due to the long taxi time to the terminals.

"25R in Frankfurt should be pretty unpopular due to the long taxi time", also cheaper fees, so perfect for low-cost?

@mins: interesting point. Haven't looked at that yet. But indeed, Ryanair usually parks their aircraft pretty close to 25R...

Arrival and departure runways are mainly assigned due to airport flow. Each airport has its own set of plans of which runways to use, how to taxi to these runways etc. If everybody is moving in the same direction, things go smoother.
Pilots and airliners can request a specific runway, but the request may be denied unless the aircraft has an emergency. Generally the reason is to shorten taxi time, and ATC may grant the request if traffic volume is low. For example, in an airport with a parallel runway configuration, a cargo plane may request the one closer to the cargo terminal.
At some airports, a runway switch may be performed fairly late during the approach. For example, the visual approach to 13L/13R at JFK is largely the same - the only difference is timing the final turn*. Occasionally you will hear pilots requesting the other runway on ATC recordings on YouTube.
For specifics such as which runway goes to which airline, they are local to the airport in question and outside the scope of this answer.
*occasionally, the pilots got it wrong and line up for the wrong runway


text:
How do pilots hold the runway centerline during takeoff?
Holding the taxiway centerline during taxi is usually done with the nose gear tiller in commercial aircraft. During take-off, until which speed is the tiller used before using pedals to control runway centerline alignment?


text:
What is the typical touchdown vertical speed of a large airliner?
What is the vertical speed (range) of a Boeing 787 (or any other large commercial aircraft) that should be achieved just before and during touchdown? I'm not interested in the vertical speed during the approach, my question only targets the last 100 feet before touchdown... this includes the vertical speed after the flare. Obviously a vertical speed of 0 fpm is desired for comfort reasons, but as I understand (see also this question), aiming for 0 fpm makes it difficult for pilots to aim at an optimal touchdown point on the runway.

Related but lacking in specifics: What vertical speed at touchdown makes a 'perfect' landing?

The aircraft should descend on a straight line, typically 3 degrees, up to the flare. This corresponds to a vertical speed of 600 feet per minute if landing airspeed is 120 knots; higher is possible. During the flare, nose angle increases but throttle decreases, so the effect on sink rate will depend on several factors. The following manual mentions 150 feet per minute as a typical touchdown speed.
A vertical speed of 0 is not feasible nor desirable, because descending the last few feet will take "forever." For example at VS = 20 fpm, descending the last 10 feet will take .5 minutes during which the aircraft will fly forward about 1 mile!

From 737 NG Flight Crew Training Manual, 737-600  Touchdown Body >Attitudes, Section 6, 2008.
Typical landing conditions:
• 3° approach glide path
• flare distance is approximately 1,000 to 2,000 feet beyond the threshold
• typical landing flare times range from 4 to 8 seconds and are a function of approach speed
• airplane body attitudes are based upon typical landing weights, flaps 30, VREF 30 + 5 (approach) and VREF 30 + 0 (landing)
A smooth thrust reduction to idle also assists in controlling the natural nose down pitch change associated with thrust reduction.

‘ A vertical speed of 0 is not feasible nor desirable, because descending the last few feet will take "forever." ’ – Um, Zeno's paradox? It absolutely is possible to reach the runway surface in finite time (and indeed quickly) but have zero vertical speed when the wheels touch the ground; it requires a parabola-shaped final trajectory. Now, that's probably difficult to control, and not a good idea in the first place, but this answer doesn't give the reason.

Pilots aim on attitude rather than rate. But, with that in mind, the typical touchdown is somewhere around 50-300ft/min. Anything below 200fpm in a B787 tend to feel very smooth (personally I've never seen less than 105fpm, and it was super smooth, as smooth as you can expect), different aircraft feel different. Between 200 to 300, feels normal, and above that, up to 600, feels firm. More than 600fpm you are likely to have a hard landing, but as mentioned before, that depends on the crew impression - the aircraft should stand touchdowns even harder than that. Nevertheless, as Boeing mention on tis manuals, "a smooth touchdown is not the criterion for a safe landing". Specially on wet runways, it is not even desired. So, pilots only usually try to smooth it when everything is perfect, being ready to disregard that if it compromises even a tiny bit of safety. The aim is to touch where you want to, at the speed and attitude you want to. The smoothness is totally secondary.

What are you watching to observe the vertical velocity at touchdown?

The closer to zero the better! Obviously there has to be something or you'll stay flying forever (run out of runway and have to go around) but the most comfortable for the plane and passengers is to touchdown at near zero vertical speed during the last few seconds of the flare.
EDIT: Based on user mins observation of you stating not wanting the VS on approach you can ignore the last paragraph but essentially during the flare you are going from approach VS of about 750 to a final touchdown of as close to 0fpm as possible.
As for the approach portion before the flare it can be figured out with some math based on the ground speed and the angle of the approach (typically 3 degrees on an ILS approach). I'm not going to go deep into the vector equations but there are some nice Rules of Thumb you can use to figure it out instead. For example multiplying the groundspeed* by 5. I think a 787 does about 150KIAS (Knots Indicated Airspeed*) on approach typically so that would work out to 750fpm.
[*] Of course depending on the headwind or lack thereof it will change the groundspeed and thus the rate needed to maintain the 3 degree (or whatever it is) on approach.

He said before and during touchdown. I assumed before being the approach and during being the flare. It starts from circa 750fpm and ends and as close to 0fpm as possible. I guess if he wants ONLY during the flare he can ignore the second paragraph.

Yes I missed that I guess, but regardless you are starting from about 750fpm and ending at 0fpm long story short. I did edit the answer now.

Is a VS of 0 fpm really desired? I understand that trying to achieve 0fpm results in higher comfort obvioulsy, but makes timing and aiming to an optimal touchdown point difficult...

That's why landing is an art. It is a whole bunch of compromises. The idea is to hit the aiming point as lightly as possible though.

@mins: yes, that's part of the origin of the question - but the question and answers you linked lack quantitative information.

I can probably dig out references in the (European) morning, but I am pretty certain a 0 fpm touch down is undesirable and a positive touchdown should be achieved instead, as otherwise a delay in air/ground triggering (weight on wheels) could lead to a delay of spoiler, brakes and reverse thrust deployment (these systems are normally inhibited when the aircraft „thinks“ it’s still airborne). This would be associated with an increase in landing distance with the obvious risks along with it.

I suppose if a few hundred feet will make the difference then yes, place it firmly but if you have the runway available lighter is better.

@p1l0t I‘m not sure I agree (I’m not saying that matters, either). At least in airline operations, I would have thought training objective should be to achieve as consistent a touchdown as possible every time, rather than grease it on long runways and slam it on short ones?

@CptReynolds Depends on the airline what their procedures are.

This answer is perhaps "less incorrect" in the context of light general aviation aircraft, but -1 because the OP is specifically asking about large commercial aircraft. In that context the other answers that cover the pitfalls of a too-soft touchdown are correct (and much of that applies to light GA as well).

I don't think it's that different. If you have the runway you land lightly. If you need to touchdown at a specific point then you touchdown at that point even if means less of a flare. I do the same thing in a piston or the jet. If I get it perfect I touchdown at said point very lightly. Is it more difficult coming from an ILS in low vis, or at a runway that is short or both, absolutely. Are there cases where you should be very sure not to float (or be light on the wheels), absolutely. Doesn't change the fact that landing lighter is usually the goal.


text:
How are sector capacity constraints set in the current US ATC system?
My understanding is that in ATC, one of the constraints when considering the distribution of flights is the number of aircraft occupying a sector. Each sector can have different capacities.
I have read many academic approaches on how to calculate these capacities, but my doubt is: what is the method used right now, on February the 6th 2017?


text:
Does the A320 autopilot work in flight with both engines off?
For a series of simulator sessions to determine the speed polar with students we plan to cutoff both engines in our A320 simulator, but we still want to use the autopilot to control speed (in theory, the autopilot would adjust pitch to keep a desired speed). Obviously, some modes, like altitude hold, positive vertical speed and autothrottle modes will not make sense in such a scenario.
In a real A320, can the autopilot (or selected functions only?) be used (activated) when both engines are cut off? (for example, after a double bird strike)? Assume APU running, so electrical power is guaranteed.

Talk to them about mcCready and teach to push the stick forward if in doubt :-)

From the A320 Flight Crew Training Manual:

Following an all engine flame out, the flight deck indications change dramatically as the generators drop off line. The RAT is deployed to supply the emergency generator and pressurize the blue hydraulic circuit.
Significant remaining systems in ALL ENGINES FLAME OUT
FLY PFD1, Alternate law
NAVIGATE RMP1, VOR1
COMMUNICATE VHF1/HF1/ATC1

As you can see, alternate law is available, and only one hydraulic circuit (blue) is powered by the RAT (Ram Air Turbine), not the APU.
Alternate law does not control speed with pitch, and particularly

At the flight envelope limit, the aircraft is not protected, i.e.:

In high speed, natural aircraft static stability is restored with an overspeed warning
In low speed (at a speed threshold that is below VLS), the automatic pitch trim stops and natural longitudinal static stability is restored, with a stall warning at 1.03 VS1G.

However what happens if you do start the APU then (or have it running in the first place, since you are doing it on purpose)? I believe the normal law should be restored.

@JanHudec "With RAT (loss of GEN 1 & 2) the APU is allowed 3 minutes for a start attempt" I will find more info tomorrow, but as far as I remember, you can't rely on the APU.

I have tested the scenario in our simulator. Indeed, I can activate the autopilot, and I can also activate HDG mode. As you said in your answer, speed mode cannot be activated! I wasn't sure how realistic our simulator depicts the real A320 autopilot...

@JanHudec I checked. the training manual says that the APU provides electrical power, and for the "fly" component, still only PFD1 and alternate law would be available

@ymb1 I don't have the FCOM here


text:
Which pilot (pilot flying, pilot monitoring) handles CPDLC (operates CPDLC interface)?
This question relates to commercial flights, typical two-pilot crew: In some airspaces, e.g. North Atlantic, pilots and Air Traffic Control use Controller Pilot Data Link Communication (CPDLC, datalink) to communicate instead of VHF or HF.
Voice communication is ususally handled by the Pilot Monitoring (PM, or pilot non-flying PNF) - meaning the PM does the communication, and the PF executes instructions from ATC. With regards to CPDLC, which pilot handles datalink communication, is this also the PM as per standard operations? Are there standard operations for this?

With most airlines, the PM(pilot monitoring) handles datalink communication, with confirmation from the PF(pilot flying) before executing any  instructions, clearances, or changes.
As with everything, there might be some exceptions at some airlines.


text:
What is the maximum legal flight time for single pilots under Part 91/135 operations?
I'm referring to FAA Part 91 and 135 operations (or similar,  EASA) and the maximum duration of one single flight (not the maximum duty time per day / week / month). If any, what are the legal flight time limitations for single pilots? In other words, which flight time requires more than one pilot?

Short answer: no limit for private Part 91 operations, otherwise 8 hours.
The only Part 91 regulations I can see on this are in Subpart K - Fractional Ownership Operations. There's too much information to quote here, but see 91.1057, 1059, 1061 and 1062. For a single-pilot operation the basic limit is 8 hours, per 1059(b):

(b) Except as provided in paragraph (c) of this section, during any 24
  consecutive hours the total flight time of the assigned flight, when
  added to any commercial flying by that flight crewmember, may not
  exceed—
(1) 8 hours for a flight crew consisting of one pilot;

There's no restriction for typical private GA pilots, apart from 91.13 on careless or reckless operation. Flying while very tired could easily be seen as reckless if it affects the safety of a flight.
As for Part 135, the regulations are in Subpart F—Crewmember Flight Time and Duty Period Limitations and Rest Requirements. Again, there's too much to quote but the basic limit for a single pilot is 8 hours, per 135.267(b):

(b) Except as provided in paragraph (c) of this section, during any 24
  consecutive hours the total flight time of the assigned flight when
  added to any other commercial flying by that flight crewmember may not
  exceed—
(1) 8 hours for a flight crew consisting of one pilot;

Your second question about when an additional pilot is required is a bit unclear. A second pilot is usually required because of the type of aircraft or operation, not the length of a flight. But I know very little about Part 135 so I may be wrong; in any case, I think it would probably be better as a separate question.

In reference to your last paragraph, if there is more than 8 hours of flying in a day, there is the option to add a second, third, and even fourth pilot in order to take advantage of the extended flight time available to those crews.  This, of course, assumes that you have other qualified crewmembers and appropriate rest facilities for the "off-duty" crewmembers.


text:
When do pilots have to submit position reports?
While over non-radar controlled airspace (e.g. the North Atlantic, the Pacific, or over vast parts of Africa), pilots will submit position reports. Is there a regular time interval in between position reports, or is that only dependent on reaching a waypoint in the flight plan? What happens then, if waypoints are hundreds of miles apart (which would be the case for example over northern Canada)?
Can the position reports be also submitted via CPDLC (Controller-Pilot Data Link Communication)?

It depends on the type of flight rules you are conducting the trip accordingly.  In the United States, the FAA requires pilots to make position reports on IFR flights in controlled airspace where radar coverage does not exist.  When your flight plan is activated and opened by means of receiving an IFR clearance, ATC has cleared a block of airspace along your route between your clearance time and your estimated time of arrival at your destination.  Since they may not be able to follow your flight over certain segments due to a lack of radar coverage, the need to know when you have arrived at your planned waypoints and rely on your periodic updates when you reach them during your flight; if you don’t report in at these specific points within a reasonable time window, ATC may assume that something has happened to your flight and initiate search and rescue operations.
Near as I know, position reports are still done by means of VHF radio communication; they cannot be submitted to ATC by other means.


text:
When is deicing required?
For airliners, under which meteorological conditions is de-icing required?
What factors (temperature, humidity, dew point, precipitation, etc.) influence the decision to de-ice?
Is decision to de-ice down to regulations, the airline, or the captain?

Are you asking about in-flight use of deicing systems, or deicing prior to takeoff? The regulations and decision making processes differ between the two scenarios.

There are a few stages where ice prevention or mitigation is relevant. The FAA publishes a nice handbook on it here if you want more info. Very broadly speaking De-Icing activated when airframe ice is noticed. Anti-Ice is activated when a Pilot believes they may enter icing conditions. Ground based De-Ice is applied when icing conditions prevail in the area.
Before Takeoff
Most, if not all commercial airports offer de-ice facilities if geographically relevant. After the crash of Air Florida 90 the FAA took a bit of a harder stance on De-Ice and now stresses the need for mobile De-Ice units to allow planes to be De-Iced without leaving the taxi queue as well as permanent stations as they have always had. A lot of their suggestions are covered in this AC as well as this one. In this case both airline procedure and FAA regulations will dictate the need for De-Ice. Strictly speaking according to FAR 121.629 a dispatcher can hold an aircraft if they feel it is not correctly De-Iced. However by the same law a pilot can hold their own departure for the same reason.
En Route
Once in the air there are a few ways things happen, but generally its ultimately up to the pilot to activate the De-Ice system. On one hand the aircraft POH will more than likely have guidance on when to do this, however, airlines may implement further (and more strict) procedures. Some aircraft are equipped with systems that automatically activate in the presence of ice build up.
Once in route there are effectually two kinds of systems,

Anti Ice: prevents the build up of ice in the first place, heated leading edges etc. These are activated before entering icing conditions.
De-Ice systems: like boots these systems remove ice once its built up. In this case you need to actually enter the conditions and allow the ice to build up first.

Ice can form in a variety of conditions and can be dangerous or potentially fatal in some aircraft. The temperature depends on the cloud type but generally speaking low temperature and higher moisture content will create worse issues.

(source)
Pilots will be alerted to possible icing conditions via an AIRMET ZULU. These are often quite broad area AIRMET's. If a pilot believes they are potentially flying into icing conditions they should keep an eye on the airframe for structural icing build up. Many airplanes have icing lights to help at night with this. A pilot can activate the De-Ice system at any point if they feel it is needed.

Per §121.629 the flightcrew must not takeoff if the aircraft needs to be deiced. This is a regulatory requirement, not an option.

For all aircraft, structural icing can occur when moisture is present in the air at temperatures between about 4° and -10°C.
Your comments would indicate you are talking about the application of deciding fluid to the aircraft prior to departure.  The inidividual airlines may have their own protocol for the use of deciding fluid, but the decision to do so is the prerogative of the flight crew with the captain's approval.  Most likely that kind of decision is made if known icing conditions are anticipated in the flight plan immediately after takeoff.  A proper weather briefing for AIRMET sierras, temp/dew point spreads, IMC conditions with precipitation and low temperatures present all would factor in to this decision.

The decision on whether or not to de-ice is the flight-crew's to make, but that decisionmaking process is defined by 14 CFR, Operation Specifications, and approved company manuals, and must be accomplished in accordance with an approved ground deicing/anti-icing program.


text:
When is the descent clearance requested from ATC?
Is there a rule / Standard Operating Procedure as to when request the descent clearance during cruise flight? Something like one minute before reaching the Top of Descent point?

Whether there are any formal policies for when to request descent will depend on the airline. However, I doubt formal procedures are established, since it should be pretty obvious to pilots when to request descent.
From a controller point of view, I will expect you to request descent when you are ready for it - so a minute or so before reaching your top of descent point. Controllers are able to estimate when you are going to request descent, based on experience, known level restrictions and typical aircraft performance. Controllers who have been working the same sector for a few years will be able to tell pretty much exactly when a certain flight is going to request descend, based on the current wind, runway in use, airline and aircraft type. What this means to you, as a pilot, is that you can expect the controller to be ready for your request; You can normally expect to receive a clearance for descent immediately after requesting it - so there is no reason to request it several minutes in advance.
Very few pilots will request descent several minutes before ToD. If they do, I can - if traffic flow permits - use the phrase "When ready descent to FL160". You are then free to start your descent when passing the ToD. Honestly though, if you call me up and say "Request descent in 5 minutes", I will most likely just reply with "Roger, call me back when ready for descent". The traffic situation can change significantly in 5 minutes, so I don't want to issue a clearance that may not fit into the future traffic picture. In the end, the early request just costs time on the frequency, which can be a scarce resource in a busy sector.
Moral of the story: as a controller, I know my airspace very well, and I have a pretty good idea of when you are going to be ready for descent. Because of this, there is no reason to request descent before you are ready for it. If you do, it will not matter at best, and be slightly annoying at worst.
ATC can of course also descend you before your ToD for various reasons, but that is another discussion.

I agree with everything said above, adding that it might depend on the PF(pilot flying the leg) in our aircraft, our vertical path is displayed which takes in to account headwind or tailwind and in preparing the flight on the ground when loading the flight plan on the FMS we can select our descend profile i.e a standard 3° path or higher. Some colleagues prefer steeper descend so they can stay higher for longer therefore reducing fuel consumption.
Therefore it also depends on personnal preference really. Having said that, certainly in Europe, controllers will ask you to descend before you request it and the London area will even ask you to be level by a certain distance....


text:
How is the airspeed-Mach number transition handled in modern airliners?
During the climb phase, how is the transition from constant speed (IAS) to constant Mach number handled? Does the pilot flying have to manually "push the button" on the control panel, or is the transition automatically done by the aircraft? How does the pilot / aircraft know when the transition should happen (i.e., from flight plan?)
I guess it's the same during descent?

The transition happens around FL260 at which the Mach Maximum speed of the plane, intersects with the Maximum speed IAS of the plane.
For example if the maximum IAS Speed is 300 knots, and maximum Mach is 0.76, then you will fly 300 knots until Mach is 0.76, at which you will follow the Mach Number.
Descent, same thing. Follow the mach number until it intersects with maximum IAS, at which point follow the IAS down.

Did you really mean MAXIMUM IAS? This sounds like Vne.  Surely one doesn't normally climb at Vne.


text:
Which incidents did not result in accidents because of the actions of the second pilot on board?
In accordance with 14 CFR §25.1523 and §121.385c3, commercial airline aircraft must be operated by at least two pilots. This provision mainly bases on workload and pilot incapacitation considerations (see §25.1523-1).
I am looking for any incident reports of events, in which the second pilot (irrespecive of rank) on the flight deck has corrected a (fatal) mistake made by the other pilot or discovered a failure of some sort which was not discovered by the other pilot, and thus averted an accident. So not the daily flight in which everything is normal, but those in which something went wrong which was then corrected by the second pilot.
Mostly, only events in which something goes wrong and which turn out as severe incidents or accidents are reported as such. These events are thoroughly investigated to learn from these events and make aviation safer. I am, on the other hand, interested in the other 99,99..% of events. Those events that are rarely reported, because everything turned out well in the end, "almost-accidents" that were prevented by the second pilot on board.
Besides the obvious pilot incapacitation events, can anyone recall any specific events / flights and direct me to the respective (official or non-official) report, i.e. by the U.S. NTSB, the French BEA, the German LBA, the British & Australian CAA, …?

@mins: in general, yes, but let's keep it open. Could also be that the Pilot Monitoring makes a mistake in his area of responsibilty (i.e. ATC communication, preflight checks) that leads to an incident or even worse and "the other pilot" discoveres it and corrects it to avert an accident.

Lack of coordination between PF and PM has been fatal in at least one accident (AF447) where inputs on sticks were opposite and led to reduced action on the elevators.

@mins - exactly. But I am interested in these events that did NOT result in an accident due to the actions of a second pilot...

@mins This is the opposite of what is asked: A case where the actions of one pilote might have saved the plane, but the other one prevented it.

@Antzi: sorry, I know this is a tough question. It's not about trying to save the plane and preventing saving it, it's about preventing an accident (preventing the first pilot from NOT SAVING the aicraft, if you will)

It's going to be really hard (but not necessarily impossible) to find an answer, largely because the nature of aviation accidents is that one single mistake rarely is fatal - the Swiss cheese model. I suppose something as simple as a data entry error could bring down a plane, but if that was picked up in the normal pre-flight checks by the second pilot we wouldn't hear about it.

If you include flight instructors taking the controls to prevent students from doing something dangerous, this probably happens every day :-) More seriously, if the second pilot's intervention prevents an incident then things are working as intended so there's probably nothing to report anyway. A better source for 'incidents that didn't happen but could have' may be the NASA ASRS system or equivalent; see these reports, for example.

Related: Error-challenging Strategies: Their Role in Preventing and Correcting Errors exploring the 1982 Potomac River accident.

Does that count: "When the A320 had reached about 110 KIAS the crew spotted the A330 crossing the runway edge, the first officer applied brakes briefly, the commander took control of the aircraft, applied TOGA and accelerated the aircraft to 130 KIAS then rotated the aircraft at 7.03 degrees/second rate and climbed the A320 over the A330"? (link)

@mins Although I haven't checked the link you provided yet, that looks like what I am looking for, yes! Thank you! From that citation it looks like the action of the Captain has averted tragedy, and that the accident would have happened if he had not taken action.

The link to Aviation Herald article which the quote comes from.

@mins: According to the article, stopping would have also worked, perhaps even been safer (“permitting the aircraft to stop more than 200 meters short of H3 had takeoff been rejected abeam H4 at about 110 KIAS” vs. “wingtip to wingtip distance was 13 meters” in reality). So it doesn’t seem to be a case for this question.

So I'm chained down on the carrier deck, sitting in co-pilot seat, and another taxiing aircraft starts sliding in high winds and heavy seas, heading for my prop. I feather the prop immediately, and the plane slides into my prop arc right after it stops rotating. No harm - no foul. The pilot (also PIC) would have never seen it. Does that count?

During the 2005 Logan Airport runway incursion, the First Officer noticed the other plane and realized that they could collide. Telling the Captain to "keep it down", he pushed the control column forward and passed under the other aircraft as it took off.
During United Airlines Flight 232, the actions of the flight instructor for the type, Dennis E. Fitch, brought in additional expertise that significantly contributed to success. E. Fitch joined the crew during the flight as an additional pilot.
On the day before Lion Air Flight 610 crash, that plane, already with problems, has been saved by off-duty pilot who correctly identified the problem (and suggested to disable the flight control system).

For the third example - I believe it wasn't just a suggestion - they were experiencing the problem, and he told them how to disable it - the pilots had not been trained to do so.

I feel like there was a post on Aviation.se about that off-duty pilot who solved the issue the day before the Lion Air 610 flight, but I can't find it anywhere. Can anyone else?


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Why is the V1-speed callout automated in modern commercial aircraft while VR is not?
In some modern aircraft such as the Airbus A380 or Boeing B787, the callout of the V1 speed is automated through a synthetic voice, based on the V-speeds entered into the flight management system. However, the rotate speed VR is still announced by the Pilot Monitoring. Why is the VR callout not automated?

It would seem that calling out V1 is more of an alert and would help being announced automaltically while Vr is not.

from my experience (A310, A320 family, A340), V1 and VR speeds are often very close together, sometimes they even are the same.
The automatic callout system can only output one signal at a time; during landings, one can often hear the decreasing radar altitude callouts being overlapped. Therefore, the VR callout would often supersede the - more safety relevant - V1 callout.

That doesn't explain why automated call outs are not used when V1 and Vr are 10 knots or even more apart. Wet or contaminated runways usually produce a large split in V1 and Vr speeds.

@MikeSowsun I think it does. You want consistency, you don't want the PM going "now on this flight am I supposed to verbalise the call or will the computer do it?"

When V1 and Vr are close together, the automatic call out could easily be programmed to call out "V1, Rotate", in quick succession,  just as the pilots do.  There must be another reason why the manufacturers have chosen not to do it.


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How many radio transmissions per hour occur on a given frequency over Europe and North Atlantic?
For one of our research projects, we want to simulate a north atlantic flight from Frankfurt, Germany to the U.S.. To make it realistic, we are also simulating air traffic control - both instructions and clearances for the flight to be simulated as well as for all other flights on the same frequency. Now we were wondering, how "dense" is voice radio chatter over Europe (mainly Maastrict UAC and Scottish UAC) and over the North Atlantic (with CPDLC - Controller Pilot Data Link Communication in use)? In other words, how many transmissions per hour do pilots listen to in the given regions (approximately and in average)?
Please note, this question is not only about radio transmissions regarding the own flight, but transmissions from all flights on a given frequency that pilots listen to.
While this likely depends heavily on day and time, let's consider a typical weekday, departing Frankfurt around 10am local, so a time frame 1000Z - 1400Z for the above named regions would be of interest.
Can anyone, potentially a pilot regularly flying such a route, give some estimates?

I can't answer your question directly but as part of your research it might be a good idea to have a look at www.liveatc.net where you can listen in to ATC broadcasts live. You could even count the transmissions yourself and it'll give you a good idea of what goes on in the air.


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Do special procedures exist for commercial pilots flying over Russia?
Since Russia, and in particular the Asian part of it, is huge, I was wondering if there are special procedures for commercial pilots to follow over Russia (in particular and specifically Siberia and other sparsely populated parts)? (Except that they use the metric system.)
Does Russia provide radar coverage and flight following services over its entire territory? As an example, do the use procedures like the North Atlantic Tracks, or do pilots implement their "own ATC" by stating position reports regularly, just like over some parts of Africa?
Or is flying over Russia comparable to flying over any other European / U.S. / ... country with continued ATC service?


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What is the farthest commercial flight on a B737-800 currently?
Can anybody name the airline, distance and respective city pair of the farthest (not necessarily longest) nonstop flight on a Boeing B737-800 (currently or in the past)? I'm not interested in empty delivery or ferry flights, but in revenue, commercial flights with this aircraft type.

I believe this is GOL's Orlando->Brasilia flight at 3,778 miles. Prior to that it was Newburgh to Bergen at 3,456 miles.
Lufthansa has a 737-700 but it is a Boeing Business jet equipped with extra fuel tanks and only 86 seats which makes a Frankfurt to Pune 4,158 mile flight.
Source

Thank you! Actually, Lufthansa 's flight to Pune was operated by Privatair and was discontinued in July. Beginning November 1st, they will use an LH A319 in this route, making a fuel stop in Baku each way. https://onemileatatime.com/lufthansa-is-launching-the-worlds-worst-flight/


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What is the process to disconnect ground electric power before pushback?
While commercial airliner are parked at the gate, they have electrical power connected to the aircraft (if available at the airport). This needs to be disconnected before pushback - what is the process to do so?

How does the ground crew know it is safe / ok to disconnect ground power? (ask pilot if Auxiliary Power Unit (APU) is running?)
When will it be disconnected? As late as possible before push-back?

Thanks!

When is the GPU disconnected?
Airports have rules regarding APU use, to reduce noise and pollutants near airport gates.
Airline operating procedures usually specify when to start APU and engines. The idea is:

GPU energy is cheaper than APU energy.
Using the APU adds maintenance costs.

Hence GPU is used until the first engine is started, usually when hydraulic power is required for braking. That means GPU is disconnected just before pushback.

Airbus ECAM, generators status indicating GPU is currently providing energy. Source.
Disconnection
On the aircraft external power receptacle panel there are usually lights to indicate whether an external source is connected and in use.

B737 external electrical panel, source
To prepare for pushback, the crew make sure the APU is delivering electrical power, and isolate the GPU from the electrical bus to ensure no current is drawn from it.
The ground operator prepare to disconnect conditioned air and ground electrical supply. They check the white light indicates the aircraft is not using the GPU, and operate a switch on the plug to electrically disconnects the ground supply generator from the cable. The "CONNCT" light goes off and the cable is physically disconnected from the aircraft.
More on ground handling procedures: Cello Aviation B737 procedures.
Cable and plug
The GPU cable/plug contains 4 power conductors and pins: The three phases (A, B, C, also called "lines") and a neutral/ground (N or G).
However the cable has a specific design due to the presence of high currents and 400 Hz. Reactance is proportional to frequency. At 400 Hz cable reactance is 8 times the reactance at 50 Hz. While it doesn't generate heat like a pure resistance it still creates voltage drops.
A large part of this reactance is due to the strong magnetic field around the wires, itself resulting from the strong currents. This reactance varies when the cable is bent, due to the changing geometry of the field, leading to corresponding voltage variations.
The cable shows two other problems:

Large diameter conductors required by the high currents leave empty spaces in the cable section.

The significant skin effect at 400 Hz prevent electrons to reach the wire center, so using a large diameter is not effective to get a low resistance.

Fortunately enough these three problems can be mitigated with multiple smaller wires for each phase, still connected to the same pin of the plug. Usually two wires are used per phase and wires are distributed around the neutral so they cancel each other magnetic field:

Source
A, B, C, N/G are available at the corresponding pins of the plug:

Plug (source)
For the scale, the four largest holes have the diameter of a finger. You may also notice two smaller pins labeled E and F.
E/F control pins
For a 90 kVA GPU, each phase can provide 30 kVA at 115 V RMS, requiring 260 A RMS current.
If the connection is broken when such current flows, arcing occurs between the disconnected parts. They can melt down, and liquid metal can be projected around.
Just bear in mind the principle of hot disconnection is the one used for arc welding, with currents usually less than 300 A. But arc welding with 260 A on an aircraft is not recommended. In an accident involving a A320, where a power wire disconnected from a damaged plug (comparable to disconnecting the plug with power), the BEA noted:

At this moment, witnesses heard an explosion, the ground attendant saw an electric arc of around 30 cm at the connector and the ramp agent was thrown to the ground.

To prevent arcing, the GPU plug is fitted with a protection against hot disconnection. Two pins (E and F) of the cable plug are used for status exchange between the aircraft electrical system and the GPU. These pins are shorter than the power pins, therefore in normal conditions they are disconnected a short time before the power pins.

Source
This way, when the plug is disconnected, both the GPU and the aircraft can sense it and stop generating/using power to/from the corresponding plug before the first power pin is actually disconnected, preventing arcing.

Source
Additional features
Control wires can be used to connect optional systems to the GPU:

Red/green (ON/OFF) push-buttons for remote control of the GPU.

E/F pins fitted with a small switch to know when the cable connector is 90% inserted within the aircraft panel socket and the connection can be seen as established.

When the cable comes from the loading bridge, additional push-buttons for reel control: UP/DOWN, IN/OUT.

Sensors to detect reactance variation, hot cable/plug or broken neutral.

Conversely, LEDs on the plug can be switched on or off by the GPU using the control wires.
More information:

AXA 2300 GPU Manual

Interesting that the image showing the cable layout is circular with 7 primary conductors, yet the connector you show is rectangular with only 6 connectors. Can you explain the difference or is that scope creep?

@FreeMan: The two A conductors are connected to the same point at each end of the cable, same for B and C. This is just a way to move electrons for each phase such that no (inductive) reactance is created by having an homogeneous magnetic field which cancels itself. The two small pins are for ON/OFF remote control.

Ah! That makes sense. The green connector, then, actually has 2 extra pins (A, B, C, G, x & y) that, presumably, connect the various and sundry small wires shown in the somewhat generic cable cross-section.

Yes, the two extra pins are to remote control the GPU from the aircraft interface.

"Currents required for 90 kVA under 115 V are about 100 A" your numbers seem to be off, 100A * 115V is 11.5KVA, even if we assume that it's a 115V P-N (~400V P-P) and the 100A is per-phase that still only adds up to 34.5KVA.

@PeterGreen: Correct, this figure is wrong. The relevant value should be the P-N intensity in the last phase assuming other phases have already been disconnected. With this completely unbalanced system, assuming other protections didn't work and ignoring effects created by the sudden raise in current, that would be around 1 kA. P-P is 200 V ($\small \sqrt{3} \times 115$).

Delivering 10kVA as 1kA at 100V (and at 400Hz) is insane! What on earth went on that such a mad standard was dreamt up? And I thought the railways excelled at shooting themselves in the foot, electrically!

@Dannie, sometimes they shoot themselves in the ear. 100kVA, not 10. Those cables are designed to sustain 4 kA per phase during 5s (300 A in normal use), while the temperature climbs to 200°C

@Dannie Aircraft use 400Hz AC because the transformers are lighter than 50-60Hz ones, and 110V because the standard was developed in the US.

@StephenS: Ah this transformers legend found in many answers including on this site... 400 Hz was chosen for electric motors torque and speed and was practical for the constant speed generator, not to save 10 kg on a transformer.

@StephenS the higher frequency does make sense for the size of the magnetics, but going upto 400Hz from 50/60Hz is such a minor win (compared to the 100kHz kind of region you have in switching regulators) that the motor thing does seem more plausible historically. It's the Volts/Amps balance that seems crazy. If you're already changing frequency, changing voltage to, say, a much saner 1kV 100A for the same power is relatively little work and would save so much in terms of thermal/copper. I think it has to be all about history. I mean no one is charging EVs like this!

@Dannie: 60Hz, 180Hz, 240Hz, 360Hz, 400Hz and 800Hz were initially considered [...] the frequency selection must take into account also the generator operating speed [...] suitable frequency values were 400Hz and 800Hz. The Army Air Corps in 1943 chose 400Hz as the standard frequency, since it appeared to be more feasible for the generator speed (e.g. 12000rpm for 4-pole machines). This ‘standard’ [...] has been made mandatory for use by the US Air Force in 1959 (MIL-STD-704). Source.


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When are ATC frequencies preset in the radios?
I've noticed that sometimes pilots tend to present the next ATC frequency in the standby radio, and when required to switch frequencies, they can just push the frequency transfer switch to switch the preset frequency to the active radio.
When do pilots preset frequencies? I.e. tower or ground frequencies are known through the briefing material (i.e. Jeppesen charts), so they could be preselected to accelerate operations. Are there any rules as to when preselect the next frequency, is it also done during cruise flight or only in the terminal area?

The reason you put a frequency in standby is to reduce workload when you are busy. e.g. You load the departure frequency into standby when calling the tower so that you can easily change after takeoff. Garmin (and I presume others) recognize that hunting for frequencies during high workload times is not ideal and make it easy to find frequencies on your radio. The even put the ILS frequency in the standby position nav when you load an ILS approach so you don’t have to look it up.

I always preset the next frequency in the radio when flipping from standby. This is a good way to eliminate workload especially for situations like being passed off from approach to tower when you are focused on configuring the aircraft for landing. It is one less distraction than having to be heads-down in the traffic pattern fiddling with the radio knob and your chart, or trying to remember the frequency the controller gave you.

I'm not aware of any rules, hopefully others can contribute, but you can usually predict the next frequency with a high rate of precision.
For example (exact stations will differ depending on airport and airspace type) a typical IFR sequence of stations.

Clearance delivery
Ground
Tower
Departures
Sector/area
...
Sector/area
Approach
Tower
Ground

The initial tuning will put delivery in live and ground in standby.  Then as you say, just press the toggle.  When the next frequency gets dialled in is not, as far as I know, governed in anyway and is probably not even in SOPs since it is just about using the equipment more efficiently.
Say delivery has given you a clearance.  They will probably follow up with something like "call ground 129.7" for push and start".  When you are ready for push and start, toggle to ground then put the tower into the standby frequency and so on.
Frequency changes are certainly made in cruise, when passing from one ACC sector to the next. These frequencies are published in the national AIP's and visible on en-route charts.  For a sector handoff, I'd probably dial the next frequency in when the current sector instructs me to contact xyz.
It's really not a big deal if you have to contact someone unexpected.  Modern boxes with push button tuning are almost as quick to tune manually as to toggle.

Also, pilots listen to communication to other aircraft so they will hear that the aircraft ahead of them is handed over to another frequency. They anticipate to be handed over to the same frequency by putting it already in the standby box.

This answer is exactly right. There are no actual regulations addressing the matter—not under any jurisdictions that I have flown under. Any rules will be company specific, though I have never heard of any rules addressing pre-tuning frequencies.

The saying is that you Aviate, Navigate and then Communicate, so if there is a rule it is that you fit setting the next frequency in when you have time. I generally list the frequencies I will be using in order during my pre-flight preparation so I don't have to hunt for them, and in flight I enter the next frequency on the list soon after changing frequency, but that's just what works for me.
Some avionics systems let you enter in all the frequencies you will use in the order you need them before you fly, you then call them up one by one during the flight with the push of a button.

This is one of range of tricky problems that makes piloting challenging. In a small plane, often the pilot has only a single backup channel, so there is the active channel and the backup channel. If a flight condition involves more than two different frequencies need in rapid succession, it can be hectic to set the radio.
In the basic case, taking off or landing at a single airport, there is usually no problem. You might have two frequencies, tower and ground. Then, after you take off, you swap ground for ATC. This is easy.
Where it gets tricky is when there are multiple airports close to each other, so the pilot is required to do a handoff. In this case there can be a bunch of different frequencies and the pilot has to switch between them rapidly, while doing a bunch of other tasks like setting the transponder. Not only that, but the aircraft will simultaneously be doing an ascent or other maneuvers, making it even more complicated. Now, factor in that when you are taking off you have to be doing all of this, yet also be constantly alert and looking out for other aircraft.
When you have overlapping airspace, the general plan is to start with tower and ground, then you will switch to clearance delivery. As soon as you have the clearance, you set the transponder. Then you immediately switch out again for the tower in whatever airspace you are flying into. Note that this frequency cannot be programmed ahead of time, because often it is given to you by the tower you just left. So, for example, the Nashua tower will clear you to take off and say, "Contact Manchester on XYZ", so immediately after you take off and leave Nashua airspace, you switch to Manchester Tower on the frequency they give you. Eventually, when you get clear of all towers, you switch to the ARTCC.

But the Manchester tower is always the same frequency and they always hand you off on that route, so you should be able to anticipate it, no? Only large airports have multiple tower and/or separate arrival and departure frequencies to have some flexibility where they assign you.

@JanHudec I think KHMT has two different listed frequencies, 121.3 and 239.025 and 121.3 is used all the time at least for me, but in that situation I never second guess it. I always wait for the handoff and get ready to dial in whatever frequency they tell me. Playing guessing games when you have mentally budgeted 2 seconds to react is not a good idea. What you don't want to do is assume you will get some frequency, then have to scramble that one time in 100 when they give you something different. Safe flight is about reducing the unexpected from 1 out of 100 times to 0 out of 100 times.

Normal aircraft COMM radio can only tune 118.00 to 136.975. 239.025 appears to be a military frequency and not relevant for civilian flight. Otherwise, good argument though—not anticipating is safer.

I take exception to the philosophy that a pilot is better off not preparing for uncertain eventualities on the off chance—you gave a 1% chance as an example—that something unexpected might arise contrary to what was anticipated. Rather, I think that such efforts are well worthwhile and good form. If the pilot's preparations—such as tuning a radio to an anticipated frequency or briefing an expected approach—prove insufficient for what turns out to be needed, no harm is done, retune the radio or brief the new approach; on the other hand, if they prove sufficient, the pilot is ahead of the game.

Also, do you mean KMHT? KHMT is on the west coast.

Regarding pre-tuning frequencies, my personal view as a professional pilot: I have always found it helpful to anticipate and tune frequencies. I can think of no time that I have anticipated a tower frequency and been switched an unexpected frequency. Even at the few airports with multiple tower frequencies, such KSLC, the correct frequency can usually be anticipated along with the expected runway. A few times, when VFR, I have called up approach and been sent unexpectedly directly over to tower, but that has been rare, and in exceptional circumstances.


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What are the role and responsibilities of "fleet captains"?
I understand that fleet captains are usually experienced airline captains that take over this management position and deal with training, staffing and administration of a particular aircraft type (or family). Can someone elaborate on the actual duties of fleet captains?
Besides the respective responsibilities, do they to a certain extent have directive authority over all pilots flying the respective aircraft types (like being their direct boss)?

A fleet captain basically deals with fleet specific issues. For instance if a new procedure is introduced in the company how is this going to be implemented on the fleet. The most recent example in my company has been the implementation of "RNP" approaches (GPS only approaches) that was introduced across the company but what does it mean for our fleet; where is this displayed on our specific aircrafts what calls should be made depending on the various cues we getting our aircraft etc...this is the kind of answers the fleet captain would have to give to the Chief Pilot in the this example the training department would be heavily involved as well with the respective CFI's(Chief Flight Instructors) again fleet specific. Depending on the company structure the fleet captain might be associated with daily issues or even disciplinary procedures in association with CP, HR etc...
Hope that helps :-)


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Where to find the callsigns of the en route controllers?
I am looking for the callsigns of ATC upper information region (UIR) controllers on a flight from Frankfurt EDDF to Seattle KSEA. According to the flight plan, the UIRs crossed are:

EDDV (Hannover)
EHAA (Amsterdam)
EGTT (London)
EGPX (Scottish)
EGGX (Shanwick)
BIRD (Reykjavik)
CZEG (Edmonton)
CZVR (Vancouver) and
KZSE (Seattle).

First, where can I find charts and information on the sectors within a UIR?
Second, does each sector have a different callsign, or are callsigns coupled to the UIR? For example, EGPX Shanwick will probably have multiple sectors, will the callsign be always Shanwick control? If they are UIR-dependent, what are the callsigns of the above-mentioned UIRs?